The finding comes from a study of more than 400 women with stage III ovarian cancer. Those who got some chemo doses delivered abdominally survived for an average of nearly 66 months.

That's about 15 months longer than those who only got chemo delivered to their bloodstream, write Deborah Armstrong, MD, and colleagues.

Their report is published in The New England Journal of Medicine.

Different Approaches

The women had all gotten "optimal debulking" surgery for their ovarian cancer. None had already had chemotherapy.

The women were split into two groups. All got the same chemo drugs, cisplatin and paclitaxel, but the drugs were delivered differently in each group.

One group got all of their chemo doses intravenously, meaning the drugs went into the bloodstream. The other group got some intravenous doses, and they also got doses sent straight into their abdominal cavity through a catheter.

"The catheter allows us to bathe the entire abdominal area with a high concentration of chemotherapy for a long period of time, which appears to be better at destroying lingering cancer cells," Armstrong says, in a news release. Armstrong is an associate professor at the Johns Hopkins Kimmel Cancer Center.

No one just got abdominal doses. Intravenous doses were needed to make sure the chemo drugs reached other parts of the body, just in case cancer cells had spread beyond the women's midsection.

Treatment Trade-Off

Women who got some abdominal chemo doses had better survival rates. But they had a rougher time during treatment and a greater risk of toxic effects.

Besides living an average of 15 months longer than women who only got intravenous chemo, those who got some abdominal chemo doses lived longer without their disease worsening (nearly two years, compared with 18 months for the intravenous group).

However, significantly more women in the abdominal group had severe or life-threatening side effects from their treatment. Those problems included fatigue, pain, and problems with blood, metabolism, and the digestive or neurological systems.

Five deaths in the abdominal group and four in the intravenous group were due to infections from treatment, the researchers note. They add that three of those deaths in the abdominal group also stemmed from the women's tumors.